A Cost-Efficacy Analysis Model for Physician Administered Anti-Tumor Necrosis Factor Agents in Crohnʼs Disease

Abstract

Purpose: To provide a cost-efficacy (CE) analysis of achieving remission in Crohn's disease (CD) patients following treatment with infliximab or certolizumab pegol from a payer perspective. Methods: An Excel-based CE model was developed to estimate cost per successful remission of CD using published data for infliximab and certolizumab pegol. Dosing information was obtained from the product labels. Drug costs were obtained from First Databank data for April 2008 wholesale acquisition cost (WAC). The cost for one 100 mg vial of infliximab was $604, and for one 200 mg syringe of certolizumab pegol was $658. The medical cost for infliximab infusions was estimated to be $237 per infusion based on the Medicare 2005 infusion schedule. The medical cost per certolizumab pegol administration was estimated at $37 based on HCPCs code 99212, for an office outpatient visit. The cost of adverse events was not included in the model. Remission rates, defined as the percentage of patients achieving a Crohn's Disease Activity Index (CDAI) score of less than or equal to 150, were used as the efficacy measure. A remission rate of 39.0% was reported at week 30 in the ACCENT I trial for infliximab. A remission rate of 29.0% was reported at week 26 in the PRECISE I trial for certolizumab pegol. The time horizon on the study was 30 weeks, as long-term effectiveness data are not yet available for certolizumab pegol. Results: The average cost per successfully treated patient, those achieving remission based on the CDAI score was $33,922 for infliximab and $37,324 for certolizumab pegol. Conclusion: Based on this model, the cost of a successfully treated patient is higher for certolizumab pegol than infliximab, suggesting that infliximab is more cost effective than certolizumab pegol for treatment of CD. Direct comparative trials and real world data are needed to confirm these findings.